A Royal Australian Air Force flight engineer aboard an AP-3C Orion aircraft keeps watch for debris during the search for missing Malaysia Airlines Flight 370 on Wednesday.

MH370 Search: Australian Satellite Spots Possible Plane Debris

By M. Alex Johnson

A satellite spotted two objects in the southern Indian Ocean that could be related to the disappearance of Flight 370, Australian authorities said Thursday in what they called "the best lead we have" in the search.

The objects are "relatively indistinct" but the larger of the two appears to be about 75 feet across, according to John Young, emergency response general manager for the Australian Maritime Safety Authority.

Australian Maritime Safety Authority

A satellite image of one of the objects released Thursday by the Australian government.

They were spotted about 1,400 miles west of Perth by a satellite on Sunday and "an expert assessment" of the images was received by Australian rescue coordinators on Thursday.

Addressing Parliament, Australian Prime Minister Tony Abbott said more analysis was needed before it could be determined whether the objects were from the missing Malaysia Airlines jet. However, Young called the discovery "the best lead we have right now."

Visibility is poor in the area, and two of five military planes over the search zone - including a U.S. Navy P-8A Poseidon - found "nothing" by 6.30 a.m. ET.

"The task of locating these objects will be extremely difficult, and it may turn out that they may not be related," Abbott said. However, he characterized the find as "new and credible information" in the search for the Beijing-bound Boeing 777, which disappeared March 8 after leaving Kuala Lumpur.

Young cautioned that the objects could be seaborne debris along a shipping route where containers can fall off cargo vessels, although the larger object is longer than a container.

The current images are not sharp enough to determine any markings. Better data could be obtained once commercial satellites are redirected to help out "in due course," Young said.

Military planes from Australia, the U.S. and New Zealand have been searching in a region over the southern Indian Ocean that was narrowed down from 232,000 square miles to 117,000 square miles.

Australian Maritime Safety Authority

A map released by the Australian Maritime Safety Authority shows cumulative search areas in the Indian Ocean.

"This is a terribly complex logistical operation to identify what we have found via the satellite," Johnston told Sky News Australia. "We are in a most isolated part of the world — in fact, it probably doesn't get, if I can be so bold, more isolated."

An Australian warship equipped to recover large objects was also diverted to the area, but it isn't expected to arrive for several days, he said.

But "with every lead, there is hope," Hishamuddin told reporters before a meeting with an Australian delegation.

The majority of the plane's passengers were Chinese citizens, and a spokesman for the Chinese Foreign Ministry said Beijing was "highly concerned" about the findings, the official Xinhua news agency reported.

Australian Maritime Safety Authority

A satellite image of the second object released Thursday by the Australian government.

Ziad Jaber, Alastair Jamieson Justin Kirschner and Sarah Burke of NBC News and The Associated Press contributed to this report.

NBC NEWS/GOOGLE MAPS

First published March 19 2014, 8:32 PM

M. Alex Johnson

M. Alex Johnson is a senior writer for NBC News covering general news, with an emphasis on explanatory journalism and data analysis. Johnson joined NBCNews.com in January 2000 from The Washington Post, where he was news editor of washingtonpost.com and night city editor of the print edition. He has also worked at the Knight-Ridder Washington bureau, Congressional Quarterly and The Charlotte Observer, where he was part of a team that won the 1987 Pulitzer Gold Medal for Public Service. He is a member of the National Press Club, Investigative Reporters and Editors and the Online News Association.